Cantor conceded the race with 99 percent of precincts reporting from the Richmond-area district showing him trailing Dave Brat 56 percent to 44 percent, according to the Virginia Secretary of State's website. Turnout was low.

"Obviously we came up short," Cantor said in his concession speech.

"It's disappointing sure but I believe in this country. I believe there is opportunity around the next corner for all of us," said Cantor, whose loss is all the more shocking because he's considered very conservative.

Mark Preston, CNN's executive political editor, said the defeat would have national implications since he has been viewed as ambitious and a potential speaker.

"This came out of nowhere," Preston said.

CNN Political Analyst David Gergen called it an "earthquake" that would "send shockwaves through the Republican ranks."

Graham wins in South Carolina

Although the tea party won big in the Old Dominion, it was headed to defeat in South Carolina where CNN projected that incumbent Sen. Lindsey Graham would easily outpace challengers from the right to capture his primary and avoid a runoff.

Graham had some advantages heading into the contest: He had a massive war chest -- around $8 million cash on hand, which gave him a huge campaign cash advantage over his primary opponents -- and outside groups have steered clear of the race, unlike in Mississippi where establishment and tea party groups fought.

"Leadership and problem solving comes with some political risk. You get a bunch of people running against you, but I'm here to tell you, it's very much worth it," Graham said in his victory speech.

A boost for the right

Brat's victory is another tea party blockbuster, reminiscent of its banner year in 2010 when those conservatives swept Republicans to control of the House.

Most recently, Republican candidate Chris McDaniel in Mississippi gained more votes than longtime Republican Sen. Thad Cochran and forced a runoff, which McDaniel is expected to win.

Another notable conservative takeover was in 2012 when tea party favorite Ted Cruz defeated Texas Lt. Gov David Dewhurst in the state's Senate GOP primary. Dewhurst had support of most Texas mainstream Republicans. ?

CNN Chief Congressional Correspondent Dana Bash said the outcome in Cantor's race will reenergize the tea party feuled right and disrupt attempts to bridge gaps between arch conservatives and establishment Republicans in Congress.

It could also cloud any prospects the White House and moderates might have for any legislative gains, Bash said.

"This will throw it all up in the air," Bash noted.

Most Republicans view Cantor, 51, as the most conservative member in the House leadership. Two sources familiar with the thinking of House Speaker John Boehner told Bash that it is now less likely with Cantor out of the picture that he will retire.

Voters rose up

Although Cantor dramatically outspent Brat in a race most political observers anticipated he would win, the cash advantage didn't affect the outcome.

CNN Crossfire host Newt Gingrich suggested that a large part of Cantor's constituency in Virginia's reliably conservative 7th Congressional District concluded that he wasn't listening and rose up to toss him out.

Losing, Gingrich said, was by no means the end of his political career, noting that he has a "great record," is a hard worker and could come back, if he wants too down the road.

Most Republicans view Cantor, 51, as the most conservative member in the House leadership lineup and a potential successor to Boehner.

He was President Barack Obama's chief foil in budget negotiations in 2011, a role he proudly pointed out during this campaign season.

Promised a shocker

Brat, who predicted a shocker on Tuesday, is an economics professor at Randolph-Macon College outside Richmond as his Democratic opponent in November, Jack Trammell. Trammell was nominated at a party convention.

In a phone interview with CNN on Monday, Brat argued that Cantor was more attentive to donors in New York and California and big business groups than he is to enacting an agenda based on Republican ideals.

"While he's got an eye on the speaker job, he's turned his back on his constituents," Brat said.

He noted that Cantor and other GOP leaders have dropped their free market principles and not done enough to address looming deficit problems.

Brat attempted to frame his challenge as another case of a grassroots conservative taking on the GOP establishment, a major theme in Republican contests this year.

He has tried to make immigration reform the central issue, and said Cantor's position would hurt the economy.

Brat said Cantor's campaign ads actually elevated his name and helped his low-budget campaign, which was supported by some heavyweights in conservative media.